Clamping methods and apparatus have become particularly important in a number of key types of manufacturing. For instance, clamping methods and apparatus are needed when testing computer processors, particularly processors that do not include pins, but instead include pads that require vertical force to provide functional contact between the contacts of the connector/socket and the pads of the processor. Such processors are generally referred to as LGA IC devices.
Since the manufacturing life cycle of processor packages continues to shorten as the frequency of processor upgrades and processor packaging upgrades increase, there is a heightened need to constantly develop new clamping systems. Such demands for developing new clamping systems are both costly and time consuming requirements.
Further, delays in developing a clamping system needed to beta test a new processor will typically delay testing or force developers to use an inappropriate clamping system that will likely apply inadequate force and cause improper seating of an LGA IC device into its connector/socket. Such improper seating is likely to cause inadequate electrical contact between the LGA IC device, connector/socket and the test circuit board, thereby skewing the results of processor testing. In a worst case, such improper seating of the LGA could permanently damage the contacts of the connector/socket, as well as the pads of the LGA IC device, an extremely costly mishap.
Typical of conventional clamping methods and apparatus for clamping processors such as LGA's is the use of clamping systems designed as an integral part of a given test connector/socket for a specific processor package. Such conventional LGA clamping connector/socket systems do not adequately address both minimized cycle time and required heat dissipation. Further, such conventional LGA clamps do not provide for evaluation of multiple connector/socket manufacturers' products and, therefore, cannot be used to evaluate connectors/sockets with different specifications.
Typical of conventional clamping methods and apparatus for clamping processors such as LGA's to production connector/sockets is the use of multiple threaded fasteners. Such fasteners can not be used with test connector/sockets since the threaded fasteners cause an unacceptable replacement time (cycle time) for devices and/or test connectors/sockets.
Other conventional clamping systems require the technician to provide the force needed to seat the LGA IC device into a connector/socket mounted upon a test circuit board. Such systems generally require a technician to use his or her thumb to exert such force. However, because current connector/sockets may include approximately 600 or more contacts, the total amount of force a technician may need to apply to an LGA can exceed 100 pounds, a force typically greater than a technician can safely provide. Even if a technician can provide that level of force, generally such force will not be applied in a controlled vertical downward direction. Accordingly, the horizontal forces are likely to distribute unequal pressure upon the contacts, thereby damaging those contacts that receive excessive force or force having other than a pure vertical direction.
Other conventional clamping systems used to seat processors such as an LGA IC device into a connector/socket are uncalibrated "off the shelf" clamps. Such clamps are not specifically designed for use as an LGA clamp. For example, the "Series 225" and "Series 235" clamp by DE-SIA-CO, a Dover Resources Company, of Troy, Mich., are conventional clamps that do not include mechanisms to align and adjust the clamp according to the specifications of each type of LGA and corresponding connector/socket. Use of an "uncalibrated" "off the shelf" clamp to seat an LGA into a connector/socket will generally provide an improper and misdirected level of force that results in inadequate electrical contact between the LGA IC device and connector/socket. Further, such use is potentially damaging to the connector/socket and/or LGA IC device.
Since conventional uncalibrated "off the shelf" clamping systems were not designed specifically for clamping processors within connectors mounted to circuit boards, these systems generally do not include a heat sink, or an area for attaching a heat sink. Accordingly, these conventional clamping systems used for clamping a processor within a connector while the processor undergoes testing are unable to dissipate and transfer the heat produced by the processor. Consequently, because a processor must be maintained at or below 70.degree. C. for proper functioning and since the processing of current LGA IC devices may dissipate as much as 28 watts of heat, the absence of a heat sink could prove fatal to the processor. More particularly, during such tests, processors, such as an LGA IC device, are likely to overheat and fail or perform erratically.
As a result of the above considerations, there is a need for a clamping system used to clamp an LGA integrated circuit device to a connector/socket mounted upon a test circuit board that is universal in use and is therefore adjustable to all types of LGA IC devices and connectors/sockets, is easy to calibrate and use, distributes force evenly across a processor and the corresponding connector/socket, provides clamping force in a vertical downward direction, is highly reliable and prevents processors undergoing tests from overheating and failing--requirements which, to the best of applicant's knowledge, have not been achieved with conventional clamping systems used to test LGA IC devices.